Song Yang, Cai Xiaoli, Ostermeyer Grayson, Ding Shichao, Du Dan, Lin Yuehe
School of Mechanical and Materials Engineering, Washington State University, Pullman, WA, 99164, USA.
Nanosong Systems LLC, Redmond, WA, 98052, USA.
Nanomicro Lett. 2021 Oct 21;13(1):213. doi: 10.1007/s40820-021-00732-1.
Detecting and quantifying intracellular microRNAs (miRNAs) are a critical step in resolving a cancer diagnostic and resolving the ensemble of gene products that orchestrate the living state of cells. However, the nanoprobe for detecting low abundance miRNAs in cell cytosol is restricted by either the "one-to-one" signal-trigger model or difficulty for cytosol delivery. To address these challenges, we designed a light-harvesting nanoantenna-based nanoprobe, which directs excitation energy to a single molecule to sensitively detect cytosolic miRNA. With light irradiation, the light-harvesting nanoantenna effectively disrupted lysosomal structures by generation of reactive oxygen species, substantially achieved cytosol delivery. The nanoantenna containing > 4000 donor dyes can efficiently transfer excitation energy to one or two acceptors with 99% efficiency, leading to unprecedented signal amplification and biosensing sensitivity. The designed nanoantenna can quantify cytosolic miR-210 at zeptomolar level. The fluorescence lifetime of the donor exhibited good relationship with miR-210 concentration in the range of 0.032 to 2.97 amol/ngRNA. The zeptomole sensitivity of nanoantenna provides accurate bioimaging of miR-210 both in multiple cell lines and in vivo assay, which creates a pathway for the creation of miRNA toolbox for quantitative epigenetics and personalized medicine.
检测和定量细胞内微小RNA（miRNA）是解决癌症诊断以及解析调控细胞生命状态的基因产物整体的关键步骤。然而，用于检测细胞质中低丰度miRNA的纳米探针受到“一对一”信号触发模型或细胞质递送困难的限制。为了应对这些挑战，我们设计了一种基于光捕获纳米天线的纳米探针，它将激发能量导向单个分子以灵敏地检测细胞质中的miRNA。通过光照射，光捕获纳米天线通过产生活性氧有效地破坏了溶酶体结构，大大实现了细胞质递送。含有超过4000个供体染料的纳米天线可以以99%的效率将激发能量有效地转移到一两个受体上，从而实现前所未有的信号放大和生物传感灵敏度。所设计的纳米天线可以在zeptomolar水平上定量细胞质中的miR-210。供体的荧光寿命在0.032至2.97 amol/ngRNA范围内与miR-210浓度呈现良好的关系。纳米天线的zeptomole灵敏度在多种细胞系和体内实验中都能为miR-210提供准确的生物成像，这为创建用于定量表观遗传学和个性化医学的miRNA工具箱开辟了一条途径。
